EXA performance problem

[Maarten Maathuis]

On Sun, Nov 27, 2011 at 3:55 PM, Christoph Bartoschek
<bartoschek at or.uni-bonn.de> wrote:
> Hi,
>
> I still have a huge performance problem with Xorg. One application that
> painted 2 Mio rectangles on the screen within a second or so with XFree86
> needs about a minute with Xorg.
>
> Most of the time is spent in libpixman. I've added some debug statements and
> see that pixman_raster_op is called about 7.2 mio times during my testcase.
>
> I do not think that pixman itself is the problem. It is just used too often
> by EXA.
>
> Is there anything I can do about this? Is there a better list where I can
> ask? Or do you know a person that might be interested in solving such a
> problem?
>
> Christoph
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As far as i know it basically boils down to this, rendering rectangles
is done in a software library as you observed. If your pixmap happens
to be outside normal ram then a lot of reads will kill performance.
These days the aim should be to use as little core rendering as
possible. A modern toolkit or a rendering library like cairo should
handle this far better.

-- 
Far away from the primal instinct, the song seems to fade away, the
river get wider between your thoughts and the things we do and say.